Cultural object regularly written into key piece of information (8)

I believe the answer is:
artefact
'cultural object' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how one could define the other.
'regularly written into key piece of information' is the wordplay.
'regularly' means one should take alternating letters (regularly take one letter, leave next etc.).
'into' indicates putting letters inside.
'key' becomes 'A' (musical key).
'piece of information' becomes 'fact' (I've seen this in another clue).
The alternate letters of 'written' are 'rte'.
'a'+'fact'='afact'
'rte' inserted inside 'afact' is 'ARTEFACT'.
Can you help me to learn more?
(Other definitions for artefact that I've seen before include "Thing made by human workmanship" , "not natural" , "Human-made object" , "Item made by human" , "hand-made thing" .)
